The RP-400M bookshelf speakers offer maximum versatility without sacrificing performance from a small, yet elegant audio solution. Designed as main speakers for a compact living space or surround sound to support a Reference Premiere speaker system, the RP-400M bookshelf speakers are the ideal choice for your home theater system. Features: 1” Titanium LTS Vented Tweeter with Hybrid Tractrix® Horn. 4" Spun Copper Cerametallic™ Woofers. Bass-Reflex via Rear-Firing Tractrix® port. Premium Scratch-Resistant Finish. Strong, Flexible Removable Magnetic Grille. Dimensions: 11.73” x 5.67” x 7.50”.